Program to know whether a number is Armstrong or not using Recursion.

Explanation :
Recursion means calling a method within itself until it returns a value.
(If n=153 then Armstrong = 1*1*1 + 5*5*5 + 3*3*3 i.e,
Armstrong =1+125+27=153.)

Code:

import java.util.*;

class armstrong

{

     public static void main(String args[])

    {

      int i,n,sum,m;

      Scanner sc=new Scanner(System.in);

      System.out.print("Enter a number : ");

      n=sc.nextInt(); 

      armstrong obj= new armstrong();

      m=obj.checknum(n); 

      if(n==m)

         System.out.println("It is a armstrong number");

      else

         System.out.println("Not a armstrong number");

     }

     int checknum(int n)

     {

        if(n==0)

             return 0;

         else

             return (int)Math.pow(n%10,3)+ checknum(n/10);

     }

}